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EPA WATER QUALITY DATA · CA

Is San Joaquin County Tap Water Safe in 2026?

Population-weighted grade and city-level UCMR5 risk bands for 1 WaterCheckup cities in San Joaquin County. "At Risk" means at least one analyte above an EPA limit or a regulated PFAS violation for that system. "Safe" means no such flag and a low-concern city profile.

COUNTY GRADE
F
Score 0
1
Total cities
1
At Risk
0
Safe
310K
Population served
TOP CONTAMINANTS IN SAN JOAQUIN COUNTY (UCMR5)

Most common analytes with detections (>0) across cities in this county — each city counted once per compound.

1.PFOS1 city
CITIES IN SAN JOAQUIN COUNTY
CITYGRADECONTAMINANTS ABOVE LIMITPOPULATION
StocktonFAT RISK1310K
FILTER RECOMMENDATIONS

Typical picks for households in San Joaquin County when UCMR5 shows PFAS or related analytes — same product lines we feature on city pages.

TOP PICKS FOR SAN JOAQUIN COUNTY
⚠ PFOS and related contaminants in county UCMR data
#1
Waterdrop G3P800 RO
EDITORS PICK
Waterdrop  ·  ~$849
Tankless 800 GPD, removes 99%+ PFAS & lead, 10-stage filtration. Smart faucet TDS display.
WHY THIS FOR SAN JOAQUIN COUNTY · Chosen for San Joaquin County because 1 of 1 tracked city shows at least one UCMR analyte above an EPA limit or a regulated violation — reverse osmosis removes 99%+ of PFAS and many co-occurring pollutants at the tap.
#2
Aquasana SmartFlow RO
MOST CERTIFIED
Aquasana  ·  ~$449
WQA Gold Seal + NSF 42/53/58/401. Most certifications of any under-sink RO. Removes 90+ contaminants.
#3
AquaTru Under-Sink RO
EASIEST FILTER CHANGE
AquaTru  ·  ~$375
NSF 42/53/58 certified. Quick-change filters, no tools. Compact tankless design, 4-stage filtration.
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